Display IP Addresses On The System Console *before* The Login Prompt.

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I have a bunch of VBox Linux VMs (CentOS 6/7, Debian7/8/9, Ubuntu
(14.0/16.04, Alpine) that get dynamic IPs. To get their respecitive IP addresses I have to login and run ‘ip addr’

I would like such info to be displayed on the VM console *before* the login prompt. Ideally an ASCII log + info (see below sig line). Thus, I can get the info from the VM console without having to login.

I read up on /etc/issue but adding “\4{eth0}” to the existing string does not work.

TIA for solutions/pointers

— Arun Khan

_ _
| |__ ___ ___| |_ _ __ __ _ _ __ ___ ___
| ‘_ \ / _ \/ __| __| ‘_ \ / _` | ‘_ ` _ \ / _ \
| | | | (_) \__ \ |_| | | | (_| | | | | | | __/
|_| |_|\___/|___/\__|_| |_|\__,_|_| |_| |_|\___|

lo: 127.0.0.1
eth0: 10.1.1.122
kernel: 4.10.0-33-generic x86_64

login:

4 thoughts on - Display IP Addresses On The System Console *before* The Login Prompt.

  • What does ‘man agetty’ (or whatever you’re using) on the OS in question say?

    Ubuntu 14.04 doesn’t list “\4{}” as an option and it doesn’t work, 16.04 does and it does appear there (might have to press Enter to get a screen refresh).

    If the OS doesn’t support it then you’ll have to get creative (send ‘ip addr’ output to /etc/issue at boot or periodically) to get what you want.

    —– Original Message —–
    From: “Arun Khan”
    To: “CentOS”
    Sent: Monday, October 2, 2017 3:03:00 PM
    Subject: [CentOS] Display IP addresses on the system console *before* the        login prompt.

    I have a bunch of VBox Linux VMs (CentOS 6/7, Debian7/8/9, Ubuntu
    (14.0/16.04, Alpine) that get dynamic IPs.  To get their respecitive IP addresses I have to login and run ‘ip addr’

    I would like such info to be displayed on the VM console *before* the login prompt.  Ideally an ASCII log + info (see below sig line). Thus, I can get the info from the VM console without having to login.

    I read up on /etc/issue but adding “\4{eth0}” to the existing string does not work.

    TIA for solutions/pointers

    — Arun Khan

     _               _
    | |__   ___  ___| |_ _ __   __ _ _ __ ___   ___
    | ‘_ \ / _ \/ __| __| ‘_ \ / _` | ‘_ ` _ \ / _ \
    | | | | (_) \__ \ |_| | | | (_| | | | | | |  __/
    |_| |_|\___/|___/\__|_| |_|\__,_|_| |_| |_|\___|

    lo: 127.0.0.1
    eth0: 10.1.1.122
    kernel: 4.10.0-33-generic x86_64

    login:

  • El 2/10/17 a las 22:03, Arun Khan escribió:

    This works for me in CentOS 7 (in /etc/issue)

    System IPv4: \4{ens33}

    You must replace {ens33} with the nic name you want to show. Get it with ifconfig

  • You are right, Ubuntu 14.04 does not support it and that’s where it does *not* work. I read the getty man page in CentOS 7/Ubuntu 16.04
    and implemented in Ubuntu 14.04 duh.

    — Arun Khan